How does ‘quantum teleportation’ work?

The experiment in which Chinese scientists ‘teleported’ a photon isn’t unique – such ‘teleportation’ has been carried out several times on Earth before.

The experiments work using pairs of tiny particles which are ‘entangled’ – ie they have linked properties.

Using the weird phenomenon of quantum entanglement, scientists can ‘transmit’ the information about a particle (ie whether it’s polarised) over a distance.

The particle doesn’t travel – but the information about it arrives in another place, instantly, due to scientists manipulating the other ‘linked’ particle.

It’s pretty baffling stuff – Einstein described the idea as ‘spooky action at a distance’.

Scientists believe that – while physical teleportation is unlikely – the technology could lead to technologies such as ultra-secure communications, where information ‘teleports’ from one place to another.

Is it possible to scale this up to teleport people?

In theory, there’s no law of physics which forbids using ‘quantum entanglement’ to transmit information about every particle in a larger object simultaneously.

But there are are enormous problems to overcome first – and scientists say that if teleporting people does ever happen, it will be very, very far in the future.

‘What we are teleporting is the state of a particle,’ Ronald Hanson, from Delft University of Technology in the Netherlands, said after a successful teleportation experiment in 2014.

‘If you believe we are nothing more than a collection of atoms strung together in a particular way, then in principle it should be possible to teleport ourselves from one place to another. . ‘I would not rule it out because there’s no fundamental law of physics preventing it. If it ever does happen it will be far in the future.’

So what’s the problem?

There are several very major roadblocks which mean that teleporting a human being is basically impossible – and likely to remain so for a very long time.

For a start, the amount of information inside a human being.

We can transmit information about one photon, sure – but University of Leicester students calculated how much information there actually is in a person, including the information in every cell and in a human brain.

Transmitting this information via radio waves would take 350,000 times the age of the universe (which is 14 billion years), the students said – commenting that ‘it would be easier to walk’.

Transmitting this amount of information via quantum entanglement, and then reassembling the body in another place is impossible without the invention of technologies we can’t even imagine at present.

Also, even if you could do it, there’s no reason to think that the new ‘person’ would actually be alive.

Is anyone more optimistic?

As with everything from time travel to cloning, there’s a few scientists who believe it will happen a little sooner.

Physicist and science populariser Professor Michio Kaku has said he thinks teleportation might happen in the 22nd century – although Kaku is known for his fondness for outlandish ideas such as parallel universes.

Kaku said, ‘You know the expression, ‘Beam me up, Scotty’? We used to laugh at it. We physicists used to laugh when someone talked about teleportation something like that, but we don’t laugh anymore.

‘At an atomic level we do it already. It’s called quantum entanglement. think within a decade we will teleport the first molecule.’

Kaku believes that scaling this up to larger objects – or even people – is simply ‘an engineering project’ – and that by next century, it might be possible.